Transformer.



PATENTED JAN. 8, 1907. D.

H. P. DAVIS & 'P. CONRA TRANSFORMER. APPLICATION PII JED HA3. 23, 1906.

llllllllnmfi'l'l'l'mmnuml T N ESSES UNITED No. 841,076. Specification ofSTATES PATENT OFFICE.

AND FRANK @ONRAD, OF SWlSSVALE,

WESTINGHOUSE ELEC' RIC & :MANU RATION OF PENNSYLVANIA.

ss'onmsn.

Letters Patent. Petented ien. 8, 19c? Original application filed January26, 199i, Eeriul E0. 389,903. Tiividocl and this application filed March23,1998. Burial Ho. 307353.

To all whom it may concern:

Be it known that we; Elmer P; DAVIE, a resident of Pittsburg, and FBAJTECohen, aresident'of Swissvule, in the county of Alleheny, State ofPennsylvania, citlzensofthe nited' States, have invented a new and.useful Improvement in Transformers, of which the following is especification, this application being a division ofour applies. 10 nonSerial No. 159,903, filed Jenuery 2D, 1904.

Our invention relates to electrical transformers end it he's for itsobject to provide a transformer comprising a core, 9 scconderi i 5winding, and two primary windi s of such structure and arrangement thatthe secondary winding is active or inactive, according to the relationthat exists between the cirwit-conductors to which the respective prizqmery windings are connected. J

Our invention was primarily designed for use as one member orelcmentoi eprotecting system for parallel transmissiondines, its function being tosupply secondary current 25 to a. circuit bresker-tripping device incase the current in either transmission-line reverses its normaldirection, as is fully set .forth in the hereiiibstore-mentionedapplication, oi which this application is a division; 3 but we neitherdesire nor intned to limit our invention. as regards either structure orservice relations except in so for as limitations may be imposed by anessential operative relationship of structure end function.

In the accompanying drawings, Figure 1 is at side elevation, and Fig. 2is a bottom or inverted plan view, or a transformer constructed inaccordance with our invention.

The transformer l is provided with e. lami- 4o noted core 2, which isclamped between two end plates or frames 3 by niesns of bolts 4, theplates or homes being rovided with feet 5 for the purpose of cttecningthe transformer securely to e supportingbese and holding it 45 in groperposition thereon.

he -'trsnsioriner-core 2 is provided with tlJQGlG S 6, and 8, the twoouter legs 6 and 7 being provided, respectively, with pri-' nioiry coils9 and 10, which are adopted for, 5 connection to separatetransmission-lines. The middle leg 8 of the core is preferably ofmaterially greater width then. that of the legs 6 and 7, it being hereshown epprc*-ri-.-

.windings, a secondary (winding an inetely double such. width, and it isprovided with an air up 11 approximately midwoyof its ends. he secondarywindr v of t e transformer surrounds the leg 8, an in or: that'it may hesymmetrically and economically disposed it may comprise two coils i2 and13, as indicated n 1.

By reason ofthe location of the coils i) 10 upon the core 2 and theprovision of the air op 11 in the leg 8 the rcfiegnetic =pro uced bythese coils will be entirely through the outer legs and the bodyportions of tm core so long as the coilscrc connected to circuits inwhich the cim'ents flow in the same direction. If the direction-of thecurrent becomes reversed 'in-eitherof the coils and 10, the resultantmagnetic iiux will 1 forced through the leg 8 end will induce cur rentin the coils 1,2 and 18. Not only will. there be no current induced inthe coils and 13 when the currents in the coils "3 and ii? are in thesome direction, but the relative d rection of the current in the coilsl2 and l when they are sub'ectecl to the ection of e r sultant magneticux will be dependent which of the coils 9 and 10 receives current which'is reversed from its normal direction.

' It will be understood that the transformer may assume otherproportions and dimensions than those here ecificelly shown anddescribed, siid we t erefore desire to include within the see c of ourinvention all such variations as 0 not materially change the mode ofoperation or the result.

We claim as our invention- 1.Atrlensformer-c'orehavingthreelegs,theintermediate one of which isprovided with an air-gap. 2. A transformer comprisin two primary windi sand a secondary win ing, the fluxes induce by, the primary wincl' beingnon molly in t e seine direction an the secondary winding biilgenergized onl when the directions of the fluxes induced hy the twoprimary windings oppose each other.

. 3. A transformer comprising two e core having three legs, theintermediate one which is provided with on sir-gap and. upon which thesecondary winding is pleced,- the primary windings placed, respectively,on the outer legs. I i

: 4; A trensfornier coinerising two primary sumo winciiags, av secondarywinding and score windings and one secondary winding, a prihaving threelegs the intermediate one of mary magnetic circuit of relat veiy 10wrewkick has gmatsr reluctance than the outer iucuance and primarymagnetic circuits of 20 mm and. 1.19011 which the sccondary Winding highreluctance which are ciso the magnetic 5 is placed, too primacy windingsbcing placed, circuits for the secondary Winding. respectively, on theouter le S. In' testimony whereof We have hereunto 5. A transformercomprislng & core having subscribed our names this 21st day of March,three is s, the intermediate one of which is 1906 provide with anair-gap, and a Winding on HARRY P. DAVIS.-

zo ecch ieg, those on the outer legs being pri- FRANK CONRAD. windingsso connected that they nor- F maliy induce fluxes in the same directionin Wltness .a Q tins com; the sccondcry Winding which is on thointermediate leg being 'encrgized only m fi 501N511:

r5 when the fluxes induced by the primary E Y windings opposc eachother. Witness as to Conrad:

6. A. transformer having two pi'imc 'y I 1 C. WALBORG.

